The amount on interest he earned is $5116.8
Step-by-step explanation:
Given,
Principal(P) = $16400
Rate of interest(R) = 3.9%
Time(T) = 8 years
To find the interest
Formula
Simple interest = 
Hence,
The interest =$ 
= $5116.80
Answer:
-16
Step-by-step explanation:
y = mx
-4 = 1/4x
Divide both sides by 1/4.
-16 = x